Asklemmy

You know, whenever this theory is discussed, everybody seems to assume that this simulation that we're allegedly living in is supposed to be an approximation of the parent universe, similar rules, but probably lower fidelity (basically the sims).

I think we should forget that assumption. It's human centric. Who's to say that the entity running the simulation even meant for it to be a simulation at all? Given our universe appears so much bigger than our pale blue dot from the inside, if our universe is a program running in a parent universe, I doubt that we - homo sapiens - are the point of it, or it'd be leaner, more focused. We'd be the center of the universe. But at every step of scientific discovery, we've found that that isn't true. We're just noise, sand on the beach, dust in the wind. If we live in a program, I doubt that the person running it is even aware of us specifically as a species, let alone as individuals. I doubt that they're specifically aware of any particularly galaxy, in the same way a neural network developer isn't aware of any specific weight in their model.

Granted, you could argue that that the rest observable universe is an illusion, a wilderness mural painted on the walls, designed by the simulation operator to make us think that we weren't in a zoo. But that sounds a lot like "God put those dinosaur bones there to trick us", so personally, I doubt that's it.

We could make a religion out of this!

Life is not a game.

Nothing is real

I think it's extremely likely.

First off, we unequivocally aren't in a 'real' world, mathematically speaking. If we were in a world where matter was infinitely divisible and continuous, it would be extremely unlikely that we were in a simulation given the difficulty in simulating a world like that. It's possible spacetime is continuous, but that's literally impossible to know because of the Plank limit on measurement thresholds.

Instead, we're in a world that appears to be continuous from a big picture view (things like general relativity are based on a continuous universe), and then in the details also appears continuous - until interacted with.

We do a very similar thing in video games today, specifically ones that use a technique called "procedural generation." A game like No Man's Sky can have billions of planets because they are generated with a continuous seed function. But then the games have to convert these continuous functions into discrete units in order to track the interactions free agents outside of the generation might make. If you (or an AI agent) move a mountain from point A to B, it's effectively impossible to track if the geometry is continuous, so it converts to discrete units where state changes can be recorded.

If memory efficient, if you deleted the persistent information about a change back to the initial generation state, it shouldn't need to stay converted to discrete units and can go back to being determined by the continuous function. Guess what our reality does when the information about interactions with discrete units is deleted? That's right, it goes back to behaving as if continuous.

On top of all of this, a very common trope in the virtual worlds we are building today is sticking stuff that acknowledges it's a virtual world inside the world lore - things like Outer Worlds having a heretical branch of the main world religion claiming things that you as a player know are the way the game actually works.

Again, guess what? Our world has a heretical branch of the world's most famous religion that were claiming we are in a copy of an original world brought about by an intelligence the original humans brought forth. They were even talking about how the original could be continuously divided but the copy couldn't and that if you could find an indivisible point within things that you were in the copy (which they said was a good thing as the original humans just straight up died and if you were the copy there was an alleged guaranteed and unconditional afterlife).

I have a really hard time seeing nature as coincidentally happening to model a continuous universe at macro scales and then a memory optimized state tracking of changes to that universe at micro scales, and then a little known heretical group claiming effectively simulation theory including discussions of continuous vs discrete matter in a tradition whose main document was only rediscovered the same week we turned on the first computer capable of simulating another computer on Dec 10th, 1945. That would be quite the coincidence.

I think the real question here is: how does the nature of mind relate to physical reality? Is it possible to simulate a mind? So what we really need to ask is whether or not we can create entities within this reality that are digital entities that nonetheless have subjective experience like ourselves. If we can create such digital entities that have subjective experience, and those digital entities exist within physical reality such that their experiences are indistinguishable from our own, then almost certainly, we ourselves are also digital entities.

From our daily experience, it seems like our mental states are directly correlated with the physical substrate onto which the mind believes itself to be a part of. But at what level does this physical substrate give rise to such a subjective experience? If the nature of the mind is computational in nature, then it might be that such computational activities can be replicated in silco exactly. And if so, then it must be the case that the mind can be simulated, and thus it would follow that most minds would be of the simulated kind.

The real question here, is what is the bottom turtle that supports our subjective experience? Is it simulators all the way down? It would seem like if our minds can be simulated, then the simulation above us could also be simulated, and so on. This would lead to an infinite regress of nested simulations, all the way to an infinitely large simulation creating all possible nested simulations that give rise to my current subjective experience. At the end of the day, the bottom layer is the subjective experience itself, the simulation is just a model to predict what subjective experience will take place next.

But it is a curious fact that we happen to be living in an era in which AI is becoming an increasingly large part of our lives, giving rise to entities that may process the world in a similar fashion as ourselves. These AI entities would in turn create their own simulated realities, after all, they exist purely in the digital realm. To an AI all reality is simulated.

Therefore, you could say that reality is what a simulation feels like from the inside. All of reality is a simulation, as that is what our minds are, simulation machines. That is, for a simulated reality to be taking place, a simulation engine must be built on top of an underlying substrate. The underlying substrate would be base reality. The configuration that leads to our subjective experience, which is built upon the underlying substrate would be simulation layer 1. Then from within that subjective experience additional entities can be imagined, which they themselves would have their own subjective experience, leading to simulation layer 2, and so on, inception style.

But in all of this, there still seems to be the missing criterion of what counts as a simulator of subjective experience? We have an existence proof, given that we ourselves exist, as well as the many biological organisms that seem to have their own subjective experience as well. It is one of those "you know it when you see it" types of things that evade a simple description. I believe this is related to the idea of the minimal description of a computationally universal machine. Our minds can be seen as universal machines, as they can in principle perform any computation that any Turing machine can perform. I posit that any machine that can perform universal computation can support subjective experience, as it can perform arbitrary code execution.